Hi Lisa

Hippocampal tissue can be homogenized in 1× PBS solution containing protease inhibitor cocktail using with the help of polytron homogenizer and centrifuge at 10,000 rpm for 15 min at 4 °C. The supernatant is separated carefully and store at − 80 °C for enzyme-linked immunosorbent assay (ELISA).

Normally, serotonin requires extraction with 0.1-0.4 M HClO4.

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Hi Elmira, the protocol suggested by Meetu should work. HClO4 increases the extraction efficacy though, but ELISAs have become very sensitive. I would start with 300-500 uL for homogenisation, test if this is in the correct range for the ELISA and then dilute if needed. Hope this helps.

Again, according to my experience you only need HClO4 when using a homemade ELISA for Serotonin. For commercial assays a regular tissue homogenate suffices.